sagemathgh-36630: Allow to specify output directory for generated interpreters
    
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Add the possibility to specify the output directory where the generated
interpreters files will be created. This is preparation for the
compilation with meson.

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URL: sagemath#36630
Reported by: Tobias Diez
Reviewer(s): Matthias Köppe, Michael Orlitzky, Tobias Diez

Author: Release Manager

src/sage_setup/autogen/__init__.py

@@ -1,6 +1,7 @@
 import os
+
 from . import interpreters
-from sage.env import SAGE_SRC
+
 
 def autogen_all():
     """
@@ -9,6 +10,7 @@ def autogen_all():
     Return a list of sub-packages that should be appended to the list
     of packages built/installed by setup.py.
     """
+    from sage.env import SAGE_SRC
     interpreters.rebuild(os.path.join(SAGE_SRC, "sage", "ext", "interpreters"))
 
     return ['sage.ext.interpreters']

src/sage_setup/autogen/interpreters/__main__.py

@@ -1,9 +1,11 @@
-from __future__ import print_function, absolute_import
+# Usage: python -m sage_setup.autogen.interpreters <output_dir>
 
-import os
-from sage.env import SAGE_SRC
+import argparse
 
 from . import rebuild
 
+parser = argparse.ArgumentParser()
+parser.add_argument("output_dir", help="Output directory")
+args = parser.parse_args()
 
-rebuild(os.path.join(SAGE_SRC, "sage", "ext", "interpreters"))
+rebuild(args.output_dir)